I can confirm, the same thing is happening on my devices ( omega2+ ) After 14 hours of head banging i made them work on a cisco router, however on mikrotik the omega2 won't even aquire an ip address . No errors in logs, nothing. I'm completely baffled . I have absolutley no idea what could even be wrong . All i can say is "piece of crap". All other devices, including raspberry pi all versions, esp8266, esp32, orange pi and many many others are working perfectly fine . The only one NOT working is onion omega2+ .

I have found the issue with the web setup and the real reason why no one seems to be able to connect the device to any wireless network. What i did, in steps, so anyone can reproduce .
1 - Reset the device to factory defaults ( VERY IMPORTANT if you tested and failed to setup wireless before ).

2 - immediately after successful boot, connect to the WIFI AP that Omega2+ sets up, but DO NOT connect to the web setup.

4 - Remove the line 'option country 'US' . If you will read the OPENWRT documentation, you will see that this setting is NOT mandatory, but it has an adverse effect for anyone that has the router set to any NON-US country. Apparently, the devs from Onion live under the impression that there is only US in this world.....
Save the file ..

5 - reboot the device, connect to the wireless AP set by the device, and run the web setup. For me it was successful , but i will gladly help anyone, as the admins from Onion seem to be clueless ...

This is beyond frustrating and idiotic . I have been modifying small routers with DD-WRT for years, setting up everything in config files, without the aid of any web or graphical interface.

I have ~15 years experience with linux and unix systems , yet for the past four days i'm banging my head against the monitor , setting up a device that is supposed to be "beginner friendly" .

This is bad engineering to say the least, and disrespect for the people who bought this device .
Do not consider this post as a rant, but rather a wake up call for those who built and sell this device .
Either stick to your claim that this device is beginner friendly, of say the goddam truth that even expert level will find this difficult and confusing.
And for the love of god, write BIG on the disclaimer "WE DO NOT HAVE DOCUMENTATION" . Besides an youtube clip and some truly misleading tutorials, there is nothing useful.
Advanced documentation on config files ? - We don't have that ! The documentation you published is NOT accurate !!